For high voltages, such components are generally constituted firstly by the cut-off units disposed in one or several cut-out chambers placed in the upper portion of the apparatus and secondly by insulating supports through which there pass the operating rods of the cut-out units. In service, the cut-out chambers and the supports are assembled so that they are sealed from the outside while inter-communicating internally. However, for transport or maintenance, it is advantageous to be able to separate these various components while ensuring that each of these components remains sealed on its own.
Thus, French patent application No. 74 17 453 of May 20, 1974, (corresponding to U.S. Pat. No. 4,016,383 and Indian Pat. No. 144, 945), describes sealing devices which allow very high tension cut-out apparatus to be assembled or dismantled in a factory or on an operating site without requiring the components of the cut-out apparatus to be drained, pumped down to a vacuum and refilled. However, before any dismantling operation, these devices require a longer stroke to be provided for the moving equipment of the apparatus beyond the normal end of stroke position. In practice, this makes it necessary to remove the end of normal stroke stop before being able to separate the operating rods from the cut-out units.
Preferred embodiments of the invention provide a device enabling assembly of cut-out apparatus components containing fluid under pressure, and separation of the assembled components, without entailing modification of the end of normal stroke of the moving parts of the cut-out apparatus.